Starter mechanism



May 19, 1931. E. FRQ'MM 1 85,9 44

STARTER MECHANISM Filed Dec. 26, 1929 2 Sheets-Sheet 1 ml m l lljlllll 'l VMIIMHM y 19, 1931- E. FROMM STARTER MECHANISM Filed Dec. 26, 1929 2 Sheets-Sheet 2 Patented May 19, 1931 I v UNITED STATES EDWARD FROMM, or ,rowArALLs, irowjn STARTER M icI'i NI M, I if Application filed December 26,1929. Serial No. 416,665.

This invention relates to the transmission mechanism of self-starters such as used in connection with internal combustion engines. The inventionis designed prlmarlly v 6 as an improvement upon the well-known Bendix drive and it has for an object the elimination of many of the screws hereto fore required and which have frequently been sheared off under excessive strain.

materially reducing the danger of breanage.

A further object is to provide the trans details of construction hereinafter described 7 c and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of' the invention.

In the accompanying drawings the pre ferred form of the invention has been shown.

In said drawings,

Figure -1 is a side elevation of the structure, a portion of the gear of the flywheel being shown.

Figure 2 is a longitudinal section through the transmission, the motor shaft being shown in elevation.

Figure 3 is a section on line 33, Figure 2.

Figure 4 is a section on line 4-4,.Figure 2. v v

Figure 5 is a plan View of the springengaging collar adapted to be secured tothe motor shaft.

Figure 6 is a plan view of the springactuated clutch member.

Figure 7 is a plan view of a portion of thescrew, the clutch member at one end thereof, andthe gear mountedon the screw.

Referring tothe figures by characters of reference, 1 designates the shaft of the start- Another object is to subject the spring to a more direct pull than heretofore, therebyer motor, the same being mounted in-the usual or any preferred manner and being provided with a collar '2 fastened thereto by a pin 3 or thelike. Thiscollar 'hasa short lateral flange 41 at the 'margin thereof formed with a slot5 in which is seated-thehookedend 6' of a flat coiled spring 7 the inner convolution of which engages the hub 8 of'a clutch member 9, This hub is mount ed'to rotate freely on the shaft 1 and'is-provided with an annular flange 10. The

spring? is adapted to be housed between this flange and the collar 2. On the flange is formed a stop lug 11 disposed inthe path of the flange 4:. 1 i e I A'screw'12 1n the formof a sleeve is mounted forrotation on the shaft 1 and is provided; atone end, with a clutch member 13 having an annular flangell. A cushioning springll5 is 'interposedbetween the flanges 10 and 14 andserves to hold them normally pressed apart without, however, entirely removing the clutch members'9 and 13 from engagement with each other.

' A gear 16 ismounted'on and'engagesv the screw 12 and has aflange 17 at one end which bears normally againstthe flange 1 1.

Thefree ends of the teeth onthis gearare If the tensioning of the spring fails. to properly start the hub 8 and clutchmember 9 the flange 4 will come against the lug 11 and positively actuate the parts although with v.

a greatly reduced blow against the lug. Ito T if tation of clutch member 9 will result in rotation of clutch member 13 and as the screw 12 will revolve therewith thegear 16 will be shifted longitudinally of the screw into will not roperly operate, the continued rotation 0 screw 12 will cause said screw to feed backwardly within gear 16 and against the action of the cushionmg spring 15 until gear 16 has been brought properly into register with the teeth on the flywheel and can move into mesh therewith. Thus .dangeriof strippingthe gear te th is practically eliminated.

By providing the fiat coiled spring 7 a more direct pull is transmitted from' the shaft- 1 to the clutch members than is possi ble with other types of spring and'dangerof breakage is greatly reduced.

By providing the catch or lug 11 the spring 7 is relievedfrom excessive strain because, after it has beenbrought to a predetermined tension, motion will be transmitr ted positively from, the flanget to the: lug 11 and clutch member 9. a 7 What is claimed is: I

A transmission mechanism for self starters of internal combustion engines including a power shaft, a collar secured thereto, a

flange projectingfrom one face of the collar, aiclutchfmember mounted for rotation on; the shaft and constantly thrusting againstthe collar, an annular flange thereon, a stoplugon said flange in the pathof the flange on the collar, a flat spiral spring secured at the end of its, outer convolution to the flange on the collar and having its inner convolution. secured to the clutch member, said spring be-ing held between the collar and the flange on the clutch member, a screw threaded. sleeve slidably and I rotatably mounted on the shaft, ,a clutch 'member at one end thereof in sliding engagement with the first named clutch member, gear threaded on the. sleeve, and a cushioning spring between and pressing inopposite directions against the clutch members Intesti'mony that. I claim the foregoing as my own, I have heretoaffixed my signature.

1 EDWARD, FROMM. 

